Looking for a tripod thats no bigger than 30-40cm when folded or less

The Manfrotto BeFree should fit the bill. It's 40cm when closed and a maximum height of 144cm with the column extended. I like it as it has lever locks rather than twist locks on the legs and I had a lot of Manfrotto heads and plates at the time. I've only replaced mine as I wanted CF and moved to ARCA/Swiss plates.

Am I allowed to mention that I'm selling a lightly used BeFree?

Take a look at this.. It's actually a two-in-one thing..as a small tripod it's VERY sturdy by the size of the legs.. and that alone is small and efficient.. but you also get the separate extendable longer part which is a three section extending thing which can be added to the small tripod and it can then become a much higher stand but still with good flexibility. Flexibility is maybe the word.. as you have the WHOLE lot carried in a modest size bag and you then choose to use either a very solid small tripod or the added legs to make for a higher tripod.. and the small tripod when folded up , makes a literally rounded body, kind of soft-padded and very comfortable to handle.... it's very good value AND for a small type pod is very usable in many situations WITHOUT taking hardly any space in luggage.. or to carry anywhere.

This is maybe a bit TOO small for you - I have one though and it comes in very handy.

How big does it need to be when it's unfolded?